Can the blood type diet heal your allergies?

What should I eat?
Each blood type evolved at different times in history. As a result, each blood family should only eat the types of food that were available at the time. Blood type O, for example, evolved 50,000 years ago, when people were hunting and gathering. According to study, this makes O-types best suited to be traditional meat eaters who don’t eat dairy products. Blood type A evolved later at around the same time that humans started to farm. So, he says, their diet was largely vegetarian. Meanwhile, blood type B evolved to cope with a more nomadic vegetarian lifestyle. Blood type AB, which is more rare and also the most recent blood type to evolve, is a hybrid of A and B so takes characteristics of both.

If you eat too much of the wrong food for your blood type, then a protein called lectins will cause clotting reactions in the blood, leading to allergies, obesity and general ill-health. Plus, regardless of your blood type, you’ll be more prone to allergies if you are something called a “non-secretor”.

‘Everyone carries antigens (a molecule triggering the immune system response) in their blood, but about 80 per cent of the population also secretes blood type antigens into their body fluids, such as saliva, mucus and sperm,’ explains D’Adamo. ‘These people are “secretors”. Those who can’t do this – “non-secretors” – become far more prone to suffer from immune diseases as a result. They also have difficulties removing immune complexes from tissues, provoking inflammatory conditions. As a result, regardless of blood type, they have a higher level of IgE, a type of antibody formed to protect the body from infection and that triggers allergic reactions. They also have a higher incidence of asthma and of infection.’

Science or fantasy?
In fact, recent DNA analyses show that a species of grass found in south-western Mexico is the origin of corn. Yet, according to study, these people should never have eaten corn or potatoes.

There are elements of correct medical information, but when these are linked to blood groups in a way that is not justified, you get the wrong results.

Dr Adrian Morris, allergy expert and allergist at the Surrey Allergy Clinic, agrees. ‘The concept of a specific blood group diet is a fashionable fad. The diet has no scientific basis and will be forgotten in a few years’ time. Applying this nonsense to treating allergies is very unfortunate and has never ever come up as a treatment option among allergy opinion leaders and experts. I, as an allergist, cannot endorse this type of diet as it only diverts attention away from the real issues facing allergy sufferers.’

That said, if you’re still curious as to whether the blood type diet can heal your allergies, there’s nothing to stop you trying it. Just make sure you speak to your GP or allergy specialist before you start the diet, to make sure it’s safe for you.